双层层压材料中激光超声检测方法的应用  

Application of Laser Ultrasonic Detection Method for Double-Layer Laminated Material

作　　者：朱倩[1] 裘进浩[1] 张超[1] 季宏丽[1] 

机构地区：[1]南京航空航天大学航空宇航学院机械结构力学及控制国家重点实验室,南京江苏210016

出　　处：《激光与光电子学进展》2016年第3期120-127,共8页Laser & Optoelectronics Progress

基　　金：国家863计划(2013AA041105);中国博士后特别资助(2014T70514);中央高校基本科研业务费专项资金(NE2015001;NE2015101);江苏省产学研联合创新资金(BY2014003-01);江苏高校优势学科建设工程资助项目

摘　　要：为了有效地检测双层层压复合材料中损伤的位置及其形状,提出了一种基于波数分析的激光超声损伤检测方法。在声场互易假设的基础上实现了波场可视化;分析了损伤对材料中超声波波数的影响;采用短空间傅里叶变换的方法,通过时域和频域的局部波数估计算法实现双层层压复合材料的损伤的定位成像;为了充分利用不同时刻和不同频率下的波场信息,减弱时间和频率选取对损伤成像产生的影响,采用了一种波数滤波损伤成像算法,通过对不同时刻的波场进行波数分析,根据不同波数所占的权值不同,采用波数域内加窗的方法滤除健康信号,并通过二维能量图实现损伤的定位成像。In order to evaluate the position and the shape of the damage in double-layer laminated composite material, a method of laser ultrasonic damage detection based on wavenumber analysis is presented. Wavefield visualization is realized by sound field reciprocity hypothesis. The impact of damage on the wavenumber of ultrasonicis analyzed. Local wavenumber estimation in both time and frequency domain is used, which can make the damage visible by short-space Fourier transformation. In order to make full use of the wavefield information at different time and different frequencies, a method based on wavenumber filtering is used. The method can reduce the influence on damage visualization, which is caused by the selected time or frequency. Wavenumber analysis is used for wavefield at different time in this method. Therefore, healthy signal is filtered by window function in wavenumber domain according to the weight of different wavenumbers. As a consequence, damage visualization is realized by using two-dimensional energy diagram.

关 键 词：激光光学 激光超声 损伤成像 波数分析 层压材料 傅里叶变换 

分 类 号：TB55[理学—物理]